时间:2019-01-30 作者:英语课 分类:农业与发展


英语课

AGRICULTURE REPORT - Cover Crops
By Mario Ritter


Broadcast: Tuesday, March 23, 2004


This is Steve Ember with the VOA Special English Agriculture Report.


The idea to grow a crop that improves the land and prepares it for other crops is thousands of years old. But scientists continue to search for new and better ways to use what are called cover crops.


Aref Abdul-Baki is with the Agricultural Research Service of the United States Department of Agriculture. He works at the Sustainable Agricultural Systems Laboratory in Beltsville, Maryland.


Mister Abdul-Baki has found some cover crops that resist worms that attack tomatoes. These crops are sunn hemp 1, cowpea and velvet 2 bean. They are planted during the months when the main crops are not normally grown. In states with moderate climates like Maryland and Virginia, the winter months are a good time to grow cover crops.


For tomatoes, cover crops can be planted in September. They can be turned over in the soil in May. The same method can be used for other summer crops like peppers, sweet corn, green beans and some melons.


After the cover crop is cut and turned, the result is a layer of organic material. This will provide fertilizer for the new crop. Also, the cover crop provides extra nitrogen to the soil.


Cover crops mixed with soil into mulch prevents the growth of unwanted plants. It also keeps soil from drying out and prevents the loss of soil.


In hot, dry parts of California, cover crops help keep down soil temperatures. They also reduce water loss and erosion.


Mister Abdul-Baki has shown that cover crops can save farmers a lot of money. Tomato farmers, for example, have used methyl bromide to treat their soil before they plant their tomatoes. This chemical kills many kinds of organisms that harm crops. Such treatment can increase the size of the harvest. But the government restricts the use of methyl bromide. And countries have agreed to an international treaty to ban it.


Mister Abdul-Baki has found that farmers who use cover crops with tomatoes save one-thousand-four hundred dollars per hectare. Farmers save on chemicals and also fertilizer. And Mister Abdul-Baki says the farmer produce as many, or more, tomatoes per hectare as compared to no use of cover crops.


Some cover crops provide enough seed for the next growing season. This can reduce costs even more.


This VOA Special English Agriculture Report was written by Mario Ritter. This is Steve Ember.



n.大麻;纤维
  • The early Chinese built suspension bridges of hemp rope.古代的中国人建造过麻绳悬索桥。
  • The blanket was woven from hemp and embroidered with wool.毯子是由亚麻编织,羊毛镶边的。
n.丝绒,天鹅绒;adj.丝绒制的,柔软的
  • This material feels like velvet.这料子摸起来像丝绒。
  • The new settlers wore the finest silk and velvet clothing.新来的移民穿着最华丽的丝绸和天鹅绒衣服。
学英语单词
administration of water
allowable bearing power of soil
amplifier recorder
aperture compensation
Aporosa
applicable programming
Ban Charim
bank demand draft
battery terminal
Bhagavata Purana
bordered matrix
brisk as a butterfly
building of steel frame construction
bust-up
caustic wash treating
channel synchronizing pulse sep-arator
critical set
daudin
degree of lodging
dermatosiophobia
diagonal and side cutting nippers
diffusion furnace
directory descriptor
dirty-laundry
DMMA
doughnut mix
electro rheological fluid
encouragement of afforestation on communal land
Ercis
euhemerized
fossil copals
gelb
geological research
go against sb's wish
granja
iconisms
idle oil pressure
index structure
inner core
interchangeable manufacture
international comparison project (icp)
Kefalovrysion
Kwanhla
labelled common block area
laceration of tentorium cerebelli
lactylic anhydride
Lemna paucicostata
Leontopodium rosmarinoides
locheil
Loxostomum
maier
malo-succinic fermentation
marmen alloy
medium frequency wave
midrashes
monitor call intercept facility
Musculus rectus lateralis
naso tergus
non incremental cost
nonmilled
offence of dereliction of duty
oshuns
pahinui
path-dependency
pharyngobranchial segment
phospharenite
physarum stellatum
Piazza's test
piggyback twistor memory
piperis fructus
positive phasee-sequence component
pozo
prace
pressure drive
prime bill of exchange
prudential rules
pseudo-range measurement
radiological exclusion area
rapid scanning spectrometer
Routing and Remote Access Service
seru-albumin
signature of matrix
simulation exercise
siphoneum
sleeping accommodation
structural database model
São José, Pta.de
tahsildars
the Champions League
town and country planning
tremot
ugly-beautiful
uneffective
upbar
vazimba
viramas
weight ton
wet tan
yellowish vaginal discharge
yonther
York, Kap
ZERT